Extracellular fluid of the kidney preserved by the Collins technique.

Hilar drainage fluid of dog kidneys was analyzed as an approximation to renal extracellular fluid after preservation by flushing with chilled high K-low Na solution (Collins C4) followed by ice-cold storage for 24 and 48 hr in a bath of flushing medium. Compared with the medium, Na and Cl were increased to 30 mM/liter and K decreased slightly to 93 mM/liter. Glucose decreased, whereas lactate, lactic dehydrogenase, and creatine phosphokinase increased by significant amounts in both the drainage fluid and bath. The inulin space of the undrained kidney average 37% of wet weight. Calculated intracellular Na and Cl concentrations averaged 50 and 37 mM/kg cell water while K remained within normal limits. A significant fraction of red blood cells retained during initial flushing entered the effluent during storage. Bath and effluent composition of a human cadaver kidney approximated those of a dog.